The present invention relates to a technique associated with a door mode for four-seat coupes. With this door arrangement, the rear-seat occupant can readily get off/on the vehicle while the front-seat occupant is seated. Two conventional techniques will be explained. The first technique relates to long double-hinge doors. The Renault Avantime (France; production stopped in 2004) can be taken as an example of the vehicle using this door mode. The second technique relates to long gull-wing doors. The Renault Nepta (France; released in 2006) can be taken as an example of the vehicle using this door mode. This vehicle has roofless-type long gull-wing doors.
However, in the case of the long double-hinge doors as well, the doors are required to have a good length in order that the rear-seat occupant can get off/on the vehicle while the front-seat occupant is seated. In generally used parking areas, such long doors tend to cause difficulty when the doors are opened/closed (the space between adjacent double-parked car is insufficient even for a double-hinge door). In the case of the long gull-wing doors, the solid mechanism of vertically opening/closing the heavy large doors problematically increases the weight of the vehicle. Also, such doors are imposed with limitation by the systems of parking areas (insufficient height of mechanical parking systems).
Double doors for vehicles disclosed in patent documents will be explained. The doors disclosed in Patent Documents 1 and 2 are aimed to be opened/closed in narrow and crowded places and not aimed for the rear-seat occupant to get off/on the vehicle while the front-seat occupant is seated. The illustrations indicate the normal (not long) doors of a normal two-door sedan. Patent Document 2 also essentially gives the same description.
Patent Document 3 describes an aim of resolving the issue that no measures could have been taken against the occurrence of necessity of opening each door from the opposite side. Further, FIG. 4 illustrates the doors of a truck having no rear seats. None of these three patent documents discloses a technique with which the rear-seat occupant can get in/out of the vehicle while the front-seat occupant is seated.    Patent Document 1: Japanese Patent Publication No. 61-12071    Patent Document 2: Japanese Patent Publication No. 61-58629    Patent Document 3: Japanese Patent Application Laid-Open Publication No. 63-284383